1. Field of the Invention
The present invention relates to a suction-type robot hand with a weight measurement function, which measures the weight of an object to be held.
2. Description of Related Arts
Various models of suction devices that suck and hold an object have been known heretofore. For example, Japanese Unexamined Patent Publication No. 06-107394 discloses a suction device, in which a suction pad slides and moves in the direction in which its suction is applied, with respect to a suction chamber. This suction device measures the weight of an object that is hanged by the sliding operation of the suction pad. Furthermore, Japanese Utility Model Publication No. 05-016047 discloses a suction device that sucks one plate member with a plurality of suction nozzles.
However, when the suction pad disclosed in Japanese Unexamined Patent Publication No. 06-107394 holds an object that is difficult to suck up by the suction pad in an airtight manner, not only unnecessary suction power is required, but, the weight of such an object also cannot be measured adequately. Also, referring to Japanese Utility Model Publication No. 05-016047, to change the posture of an object, the positions of a plurality of suction nozzles have to be changed. In such a case, the positions and postures of pipes that extend to the suction nozzles respectively need to be changed, and, as a result of this, there is possibility that the weight of an object to be measured changes.
The present invention has been made taking into account the above concerns, and it is therefore an object of the present invention to provide a suction-type robot hand that can adequately measure the weight of an object that is difficult to suck in an airtight manner.